Furnace



v [n2/enlan- FURNAGE.`

F. H. RICHARDS.

MM? MM MMMMM IJNTTED STATES PATENT OFFICE.

FRANCIS H. RICHARDS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO ECKLEY B. COXE, OF DRIFTON, PENNSYLVANIA.

FU RNACE.

SPECIFICATION forming part of Letters Patent No. 535,410, dated March 12, 1895.

Application filed October 17, 18 94. Serial No. 526,129. (No model.)

s Connecticut, have invented certain new and useful Improvements in Furnaces, of which the following is a specification.

This invention relates to furnaces, and has special reference to the construction and organization of furnace-chamber roofs. The object of my present invention is to provide in connection with a furnace-chamber an improved sectional roof of a composite nature adapted to be heated to a high state of incandescence, and to provide, as a component part of said roof, means for sustaining the weight, and for removably-holding together.

the several sections, of the roof; and also to prevent the melting and disintegration of the inner surfaces thereof.

In the drawings accompanying and forming part of this specification, Figure 1 is a vertical longitudinal section of aportion of a boiler-heating furnace embodying my present improvements, said section being taken in a line corresponding with the dotted line ct-o. in Fig. 2, looking toward the left hand in said gure. Fig. 2 is a vertical cross-section of the same taken in dotted line b-b, Fig. l, looking toward the right hand in said figure.

Similar characters designate like parts in both the figures.

In the preferred embodiment thereof herein shown and described, my invention consists in the combination with a furnace-chamber, of a composite roof consisting of a series of hollow roof-block-supporting beams, a series of heat-resistant roof-blocks supported upon and held in place by said beams, and having their adjacent sides normally in self-locking engagement in vertical direction and means in connection with and adapted for creating and maintaining a circulation of water in and through said beams, as will be hereinafter more fully described.

My improvements, which are applicable to furnaces of various kinds, are herein shown applied to an ordinary boiler-heating furnace having an ordinary combustion-chamber or furnace-chamber, C, and ash-pit, C', divided by the ordinary grate, G, which is supported at its rear end upon the bridge-wall, 7, and at its forward end uponthe front end Wall 3 of the furnace; said furnace having the usual side-walls, 2 and 4, and also having a boiler, B, located at the rearward end of the furnacechamber C as shown in the drawings..

The furnace-chamber roof (designated in a general way by R) in which my present invention particularly resides, consists, in the preferred form thereof herein shown, of a series of hollow metal roof-beams, 8, (preferably tubular) arranged above and in longitudinal disposition with relation to the furnace-chamber C, and a series of heat-resistant and preferably interchangeable roof blocks, 9, supported upon said roof-beams 8. As shown in Fig. l of the drawings the forward ends of the roof-beams 8 extend through and are supported by the front end wall 3 of the furnace, and the rear ends thereof are shown extended through and secured to the front plate or head of the boiler at a point below the Water-line of said boiler. This particular arrangement may however be modified without departure from my invention, it being simply necessary in so far as this feature of my invention is concerned, to provide rigid supports for the roof-beams irrespective of their connection with the boiler.

In the drawings I have shown the roof R of the arched variety, the roof-blocks 9 thereof being shown as engaging arch-blocks and practically constituting segments of a circular arch with their side faces in planes coinciding with lines radiating from a common center.

As shown in the drawings (most clearly in Fig. 2) the lower adjacent edges of the roofblocks are notched or grooved, as shown at 10, in the plane of the roof-beams, to 4form shoulders, or bearing-faces, 12, which bear upon the roof-beams 8, and to form depending portions, 13, which rest between said roof-beams with `their inner faces in coinciding planes, substantially in alignment with the lower faces of said roof-beams, as will be understood by reference to said Fig. 2.

By providing the roof-beams 8 for supporting and holding in place the roof-blocks 9, between which blocks said beams are located as shown in Fig. 2, and by constructing the AIOC).

roof-blocks in the manner hereinbefore described and supporting them upon and between said beams, I secure a very rigid roofstructure which would still be self sustaining if one or more of the roof blocks were removed, or if one or more of the roofblocksupporting beams were removed.

In the construction of furnace chamber roof herein described and shown, it will be observed that the roof-beams not only support the roof-blocks and prevent sagging or buckling of said roof, which sagging or buckling might be caused from excessive heat in the furnacechamber, but also sustains said blocks against displacement transversely of the furnace-chamber, the weight of the several roof-blocks being normally uniformly distributed over and sustained by the several roof-beams.

As is well known in this art, the furnacechamber roof, to facilitate and promote combustion, especially when usinglow-grade fuel and a forced draft, must be heated to a high state of incandescence, and with roofs of this class of ordinary construction having a series of roof-blocks so constructed and arranged as to support one another, much difficulty has been experienced owing to the chipping off, disintegration or crushing of the blocks at their inner adjacent edges caused by the melting tendency of the excessive heat combined with the effect of the crushing loads sustained by successive roof-blocks; it being well known that the intense heat during the combustion of the fuel tends to expand and soften the inner surfaces of the roof-blocks, and owing to the load sustained by each block these softened portions of the blocks are compressed more or less, and will, under varying conditions of temperature in the furnacechamber, scale off and sometimes cause the entire roof to sag or cave in.

By providing roof-beams for supporting the roof-blocks as hereinbefore described, the successive roof-blocks are relieved of the inj urious crushing loads which they would necessarily have to sustain if said blocks were entirely dependent upon their self-supporting quality.

To further improve the efficiency and last- .ing qualities of the furnace roof and to obviate, in a material degree, the injurious melt` ing effect of the intense heat upon said roof without materially imparing combustion in the furnace-chamber, I have provided means for slightly reducingor limiting the temperature of the incandescent roof without materially reducing the temperature of the interior space of the furnace-chamber. This means for reducing the temperature of the furnace chamber roof, in the form thereof herein shown, consists of a water-supply apparatus in connection with and adapted for supplying water to and maintaining a circulation of water through the several roof-blocksupporting beams.

One form of water-supply apparatus may, as

herein shown, consist of a supply pipe, P, in communication at one end with the interior of the boiler at its lower side, as shown at 15, and in communication at the opposite end thereof through the medium of a universal supplypipe,P, with the interiors of the several roofbeams 8, which roof-beams communicate at their opposite ends directly with the interior of the boiler B near the upper side thereof, as clearly shown in Fig. I of the drawings. This construction and organization of water-supply apparatus for the roof-beams S may be variously1 modied within the limits of myinvention, as it will be obvious that a circulation of water might be attained by means of some Well-known water-supply apparatus entirely independent of the boiler B.

As illustrated in Fig. l the roof R will preferably be upwardly inclined rearwardly so as to secure a greater rigidity in structure with roof-beams of the smallest practical diameter, and to promote the water-circulation within y the roof-beams.

By reference to Fig. l of the drawings, it will be seen that relatively cool water is supplied through the pipe P to the series of roofbeams 8, which roof-beams being relatively hot as compared with the temperature of the boiler tlues, will heat the inflowing water with great rapidity, which water will expand and rise and be delivered into the boiler near the upper wall thereof after the well-known manner of water-circulation induced by heat.

Having thus described my invention, I claim- 1. In a furnace, the combination with the furnace-chamber, of an arch-roof comprising a series of engaging arch-blocks whereby the roof is rendered partially self-supporting in vertical direction, a series of hollow roofbeams between the blocks and also adapted for supporting said roof-blocks in vertical direction, means for supporting said roofbeams, and a water-supply apparatus in connection with and adapted for circulating said water through said roof-beams, substantially as described.

2. In a furnace, the combination with the furnace-chamber; of an arch-roof comprising a series of interchangeable engaging archblocks whereby the roof is rendered partially self-supporting in vertical direction, and said roofblocks also having their inner faces notched or grooved longitudinally of the furnace at their adjacent side-edges; a series of hollowr metallic roof-beams extending through the notched or grooved portions of and between the roof-blocks, and also adapted for supporting said roof-blocks in vertical direction; means for supporting said roof-beams; and a water-supply apparatus in connection with and adapted for circulating water through said roof-beams, substantially as described.

3. In a furnace, the combination with the furnace-chamber, of a series of segmental roof -blocks arranged in an arc of a circle IOO IIO

IZO

above the furnace-chamber with their adjacent sides in planes coinciding with lines radiating from a common center, whereby said roof-blocks are self-supporting in vertical direction relatively to one another and prevent crushing of the water-circulatin g roof-beams, and said roof-blocks also having their adjacent inner side-edges notched or grooved longitudinally ofthe furn ace-chamber to form bearing-shoulders; a series of tubular roof- "block-supporting beams in abutment each with their adjacent sides in planes coinciding with lines radiating from a common center, whereby said roof-blocks are self-supporting in vertical direction relatively to one another and prevent crushing of the water-circulatin g roof-beams, and said roof-blocks also having their adjacent inner side-edges notched or grooved longitudinally of the furnace-chamber, to form bearing-shoulders; a series of tubular roof-block-supporting beams in abutment each with the adjacent shoulders of two adjacent roof-blocks, and thereby also adapted for supporting and holding said roofblocks against vertical movement; and means in connection with and adapted for circulating water through said tubular roof-blocksupporting beams, substantially as described.

FRANCIS H. RICHARDS.

Witnesses:

FRED. J. DOLE, M. D. CRowELL. 

